|
|
|||||||||
|
Persons using assistive technology might not be able to fully access information in this file. For assistance, please send e-mail to: mmwrq@cdc.gov. Type 508 Accommodation and the title of the report in the subject line of e-mail. Current Trends Premature Mortality due to Breast Cancer-- United States, 1984In 1984, malignant neoplasms ranked second among all causes of years of potential life lost (YPLL) before age 65* (1,2). Malignant neoplasms ranked fourth as a cause of premature mortality for men; however, they were the leading cause of YPLL before age 65 for women (2). In 1984, malignant neoplasms accounted for 21% (approximately 887,000 lost years) of all YPLL before age 65 among women. Breast cancer alone accounts for nearly 26% of all YPLL due to malignant neoplasms among women and is the leading contributor to premature mortality in this category. White women account for 84% of all YPLL due to breast cancer; black women have the next highest total YPLL (Table 1). The rate of YPLL, however, is 13% higher among black than among white women. This difference reflects the higher age-specific mortality rate among black women under age 50 (3) and the greater proportion of all deaths from breast cancer among black women under age 65 (61% for black women compared with 45% for white women). As a measure of premature mortality, the magnitude of cause-specific YPLL is subject to both age-specific mortality rates and the age structure of the population. Any interpretation of YPLL over time must consider not only trends in the age-specific mortality rate, but also shifts in both the age structure and relative size of the population being studied. These considerations take on particular significance for breast cancer because of the dramatic changes that are now taking place in the size of the population at risk. Just prior to 1945 both the birth rate and the annual number of births began the remarkable climb known as the "baby boom." If 1945 is considered as the first year of the baby boom, then this cohort is just reaching 40, the age when breast cancer incidence begins to climb sharply (4). In 1985, approximately 57 million women were 35 years of age or older. By the year 2025, the number of women in that age group will have increased by 61%, to nearly 91 million (5). If age-specific incidence and mortality rates remain relatively stable, as they have during the past 10 years (3), the number of breast cancer cases and deaths and the annual number and rate of YPLL will increase substantially over the next 40 years (Figure 1). The projected increase in the YPLL rate begins to slow near the year 2000 and by 2010 will begin to decline with the size of the population of women under age 65. Because these projections assume no change in age-specific mortality rates, this projected decline in the YPLL rate is due entirely to a relative decline in the number of women under age 65. Since measures of YPLL are used to evaluate the efficacy of public health strategies for reducing premature mortality, the influence of dynamic populations on observed rates should not be neglected. Observed YPLL and YPLL rates must be compared to expected YPLL and YPLL rates to control for changes in the population structure. Reported by: Chronic Disease Control Div, Center for Environmental Health and Injury Control, CDC. Editorial NoteEditorial Note: According to current estimates, 130,000 women in the United States will be diagnosed with invasive breast cancer and 41,000 women will die from the disease in 1987 (6). Breast cancer accounts for 27% of all newly diagnosed female cancers and 18% of female cancer deaths and was only recently surpassed by lung cancer as the leading cause of cancer mortality among females (6). An examination of incidence rates between 1975 and 1984 reveals a small but gradual increase of about 1% per year. Overall, age-adjusted incidence rates are higher for white women than for black women, but this difference appears to be declining over time (3). The age-adjusted mortality rate from breast cancer for all females has not changed significantly in the past 10 years. Mortality rates for black women and white women are similar, although 5-year relative survival is measurably poorer among black women than among white women for the period 1975-1984. The difference is substantially reduced when the survival rates are adjusted for age, stage of cancer upon detection, and proxy measures of low-income status. Investigators have suggested that poor survival among low-income groups may be due to lower host resistance, poor access to health care, and personal health-care practices (7,8). While differences in the stage at detection do not fully account for differences in survival (3), survival is much improved if breast cancer is detected early, when it is localized.** However, only approximately 50% of breast cancers are diagnosed while still localized to the breast (3). Application of secondary prevention guidelines recommended by the American Cancer Society (ACS) and the National Cancer Institute (NCI) has great potential to reduce mortality from breast cancer (9-11). The ACS recommends that women have a baseline mammogram between the ages of 35 and 40 and annual or biannual screening mammography between the ages of 40 and 49. Both ACS and NCI recommend annual screening mammography for women age 50 and above. The ACS also recommends that all women perform breast self-examination every month and that women between the ages of 40 and 50 have an annual physical examination of the breast. Both groups recommend annual physical examinations for women over age 50. The value of these secondary prevention guidelines is confirmed by the results of recent follow-up studies of participants in screening programs. The most recent follow-up study of 62,000 women between the ages of 40 and 64 enrolled in the Health Insurance Plan of Greater New York (HIP) randomized clinical trial revealed 23% fewer breast cancer deaths among the study group than among controls (12). Follow-up of 280,000 women between the ages of 35 and 74 who were participants in the Breast Cancer Demonstration Project (BCDP) has also shown a significant advantage in survival for women whose breast cancers were discovered with screening mammography. Using data from NCI's SEER program (Surveillance, Epidemiology and End Results) as a comparison group, the 8-year relative survival rate among the BCDP group reveals 46% fewer breast cancer deaths (12). Furthermore, results from both studies show similar survival rates for women between the ages of 40 and 49. These results support recommendations that women in this age group receive screening at least every 2 years (12). Differences between ACS and NCI screening recommendations for women between the ages of 40 and 49 reflect disagreement over earlier evidence of the value of screening mammography for women under the age of 50. As results from ongoing research become available, these guidelines are likely to become more similar. Without comprehensive breast cancer screening initiatives and increased regular screening for breast cancer, premature and overall mortality from breast cancer will rise markedly over time. Comprehensive screening initiatives hold great promise for reducing mortality from breast cancer. Given our poor understanding of the etiology of breast cancer and recent evidence that screening mammography helps reduce mortality from breast cancer for women between the ages of 40 and 49 as well as those over age 50, a woman's age becomes the single most relevant factor for recommending screening. Since endorsement and referral are essential to compliance, interventions should target health-care providers as well as women in the recommended age categories. Further, the success of any screening test depends not only on its ability to achieve acceptable levels of sensitivity and specificity but also on the maintenance of a high level of quality assurance. Until screening for breast cancer becomes a routine preventive practice, mortality from breast cancer will remain an increasingly serious public health problem. References
Disclaimer All MMWR HTML documents published before January 1993 are electronic conversions from ASCII text into HTML. This conversion may have resulted in character translation or format errors in the HTML version. Users should not rely on this HTML document, but are referred to the original MMWR paper copy for the official text, figures, and tables. An original paper copy of this issue can be obtained from the Superintendent of Documents, U.S. Government Printing Office (GPO), Washington, DC 20402-9371; telephone: (202) 512-1800. Contact GPO for current prices. **Questions or messages regarding errors in formatting should be addressed to mmwrq@cdc.gov.Page converted: 08/05/98 |
|||||||||
This page last reviewed 5/2/01
|